Integrating point of care ultrasound into rheumatology practice.

A scenario-based probability approach integrating point of care rheumatology ultrasound (POCRUS) into rheumatology practice has recently been proposed as a teaching methodology to encourage greater awareness of US for practicing clinicians especially with respect to the management of overlapping clinical conditions. This article reviews the rheumatological areas where application of POCRUS substantially enhances clinical reasoning to confirm or exclude target conditions. It highlights the definitions of ultrasound-detected pathologies in rheumatoid arthritis (RA), spondylarthritis, gout and crystal arthritis, osteoarthritis, polymyalgia rheumatica and discusses the added value of POCRUS in diagnosing these conditions. It summarizes advances in predicting giant cell arteritis with sequential application of a probability score and ultrasonography. It discusses the potential for salivary gland ultrasound in the diagnostic workup of suspected Sjogren's syndrome. Other areas for POCRUS application such as in suspected nerve entrapment are reviewed.

Development of a diagnostic prediction model for giant cell arteritis by sequential application of Southend Giant Cell Arteritis Probability Score and ultrasonography: a prospective multicentre study.

BACKGROUND: Giant cell arteritis is a critically ischaemic disease with protean manifestations that require urgent diagnosis and treatment. European Alliance of Associations for Rheumatology (EULAR) recommendations advocate ultrasonography as the first investigation for suspected giant cell arteritis. We developed a prediction tool that sequentially combines clinical assessment, as determined by the Southend Giant Cell Arteritis Probability Score (SGCAPS), with results of quantitative ultrasonography. METHODS: This prospective, multicentre, inception cohort study included consecutive patients with suspected new onset giant cell arteritis referred to fast-track clinics (seven centres in Italy, the Netherlands, Spain, and UK). Final clinical diagnosis was established at 6 months. SGCAPS and quantitative ultrasonography of temporal and axillary arteries with three scores (ie, halo count, halo score, and OMERACT GCA Score [OGUS]) were performed at diagnosis. We developed prediction models for diagnosis of giant cell arteritis by multivariable logistic regression analysis with SGCAPS and each of the three ultrasonographic scores as predicting variables. We obtained intraclass correlation coefficient for inter-rater and intra-rater reliability in a separate patient-based reliability exercise with five patients and five observers. FINDINGS: Between Oct 1, 2019, and June 30, 2022, we recruited and followed up 229 patients (150 [66%] women and 79 [34%] men; mean age 71 years [SD 10]), of whom 84 were diagnosed with giant cell arteritis and 145 with giant cell arteritis mimics (controls) at 6 months. SGCAPS and all three ultrasonographic scores discriminated well between patients with and without giant cell arteritis. A reliability exercise showed that the inter-rater and intra-rater reliability was high for all three ultrasonographic scores. The prediction model combining SGCAPS with the halo count, which was termed HAS-GCA score, was the most accurate model, with an optimism-adjusted C statistic of 0·969 (95% CI 0·952 to 0·990). The HAS-GCA score could classify 169 (74%) of 229 patients into either the low or high probability groups, with misclassification observed in two (2%) of 105 patients in the low probability group and two (3%) of 64 of patients in the high probability group. A nomogram for easy application of the score in daily practice was created. INTERPRETATION: A prediction tool for giant cell arteritis (the HAS-GCA score), combining SGCAPS and the halo count, reliably confirms and excludes giant cell arteritis from giant cell arteritis mimics in fast-track clinics. These findings require confirmation in an independent, multicentre study. FUNDING: Royal College of Physicians of Ireland, FOREUM.

Diagnostic accuracy of OGUS, Southend halo score and halo count in giant cell arteritis.

Objectives: Ultrasound has a paramount role in the diagnostic assessment of giant cell arteritis (GCA); Southend halo score (HS), halo count (HC), and OMERACT GCA Ultrasonography Score (OGUS) are the first quantitative scores proposed in this setting. The aim of this study was therefore to assess the diagnostic accuracy of these scores in a real-life scenario, as well as to evaluate their optimal cutoff, also with respect to disease extent, sex, and age. Methods: We retrospectively collected clinical, serological, and US findings of all patients referred for the first time to our vasculitis clinic in the suspicion of GCA. Results: A total of 79 patients were included, and a definite diagnosis of GCA was made in 43 patients. For OGUS, the ROC curve showed an optimal cut point of 0.81 (sensitivity 79.07% and specificity 97.22%). For HC and HS, the optimal cutoff values were > 1.5 (sensitivity 76.7% and specificity 97.2%) and > 14.5 (sensitivity 74.4% and specificity 97.2%), respectively. No relevant differences were assessed when patients were stratified according to disease extent, age, and sex. Compression sign (CS) was positive in 34 of 38 patients with cranial GCA and negative in all controls and LV-GCA. Conclusion: All three scores display good sensitivity and excellent specificity, although the cutoff was slightly different than proposed. In particular, for OGUS, a threshold of 0.81 could be employed for diagnostic purposes, although it was developed solely for monitoring. Due to its high sensitivity and specificity, CS should be always assessed in all patients referred with a suspicion of cranial GCA.

Stratification of biological therapies by pathobiology in biologic-naive patients with rheumatoid arthritis (STRAP and STRAP-EU): two parallel, open-label, biopsy-driven, randomised trials.

BACKGROUND: Despite highly effective targeted therapies for rheumatoid arthritis, about 40% of patients respond poorly, and predictive biomarkers for treatment choices are lacking. We did a biopsy-driven trial to compare the response to rituximab, etanercept, and tocilizumab in biologic-naive patients with rheumatoid arthritis stratified for synovial B cell status. METHODS: STRAP and STRAP-EU were two parallel, open-label, biopsy-driven, stratified, randomised, phase 3 trials done across 26 university centres in the UK and Europe. Biologic-naive patients aged 18 years or older with rheumatoid arthritis based on American College of Rheumatology (ACR)-European League Against Rheumatism classification criteria and an inadequate response to conventional synthetic disease-modifying antirheumatic drugs (DMARDs) were included. Following ultrasound-guided synovial biopsy, patients were classified as B cell poor or B cell rich according to synovial B cell signatures and randomly assigned (1:1:1) to intravenous rituximab (1000 mg at week 0 and week 2), subcutaneous tocilizumab (162 mg per week), or subcutaneous etanercept (50 mg per week). The primary outcome was the 16-week ACR20 response in the B cell-poor, intention-to-treat population (defined as all randomly assigned patients), with data pooled from the two trials, comparing etanercept and tocilizumab (grouped) versus rituximab. Safety was assessed in all patients who received at least one dose of study drug. These trials are registered with the EU Clinical Trials Register, 2014-003529-16 (STRAP) and 2017-004079-30 (STRAP-EU). FINDINGS: Between June 8, 2015, and July 4, 2019, 226 patients were randomly assigned to etanercept (n=73), tocilizumab (n=74), and rituximab (n=79). Three patients (one in each group) were excluded after randomisation because they received parenteral steroids in the 4 weeks before recruitment. 168 (75%) of 223 patients in the intention-to-treat population were women and 170 (76%) were White. In the B cell-poor population, ACR20 response at 16 weeks (primary endpoint) showed no significant differences between etanercept and tocilizumab grouped together and rituximab (46 [60%] of 77 patients vs 26 [59%] of 44; odds ratio 1·02 [95% CI 0·47-2·17], p=0·97). No differences were observed for adverse events, including serious adverse events, which occurred in six (6%) of 102 patients in the rituximab group, nine (6%) of 108 patients in the etanercept group, and three (4%) of 73 patients in the tocilizumab group (p=0·53). INTERPRETATION: In this biologic-naive population of patients with rheumatoid arthrtitis, the dichotomic classification into synovial B cell poor versus rich did not predict treatment response to B cell depletion with rituximab compared with alternative treatment strategies. However, the lack of response to rituximab in patients with a pauci-immune pathotype and the higher risk of structural damage progression in B cell-rich patients treated with rituximab warrant further investigations into the ability of synovial tissue analyses to inform disease pathogenesis and treatment response. FUNDING: UK Medical Research Council and Versus Arthritis.

Long-term effect of tocilizumab in patients with giant cell arteritis: open-label extension phase of the Giant Cell Arteritis Actemra (GiACTA) trial.

BACKGROUND: The combination of tocilizumab plus a glucocorticoid taper is effective in maintaining clinical remission without requiring additional glucocorticoid therapy in patients with giant cell arteritis, as shown in part one of the Giant Cell Arteritis Actemra (GiACTA) trial. However, the duration of the tocilizumab effect after discontinuation is unknown. Here, we explored the maintenance of efficacy 1 year after discontinuation of tocilizumab treatment, the effectiveness of retreatment with tocilizumab after relapse, and the long-term glucocorticoid-sparing effect of tocilizumab. METHODS: In part one of the GiACTA trial, 251 patients were randomly assigned (2:1:1:1) to receive subcutaneous tocilizumab (162 mg) once a week or every other week, combined with a 26-week prednisone taper, or placebo combined with a prednisone taper over a period of either 26 weeks or 52 weeks. Patients in clinical remission stopped masked injections at 1 year (the conclusion of part one). In part two, treatment was at the investigators' discretion and could consist of no treatment, tocilizumab, glucocorticoids, methotrexate, or combinations of these, for two years. Maintenance of efficacy as assessed by clinical remission (defined as absence of relapse determined by the investigator), cumulative glucocorticoid dose, and long-term safety were exploratory objectives in part two of the trial. This trial is registered at ClinicalTrials.gov, NCT01791153. FINDINGS: 215 patients participated in part two of the trial; 81 patients who were randomly assigned to tocilizumab once a week in part one were in clinical remission after 1 year, of whom 59 started part two on no treatment. 25 of these 59 patients (42%) maintained tocilizumab-free and glucocorticoid-free clinical remission throughout part two. Median (95% CI) cumulative glucocorticoid doses over 3 years were 2647 mg (1987-3507) for tocilizumab once a week, 3948 mg (2352-5186) for tocilizumab-every-other-week, 5277 mg (3944-6685) for placebo with a 26-week prednisone taper, and 5323 mg (3900-6951) for placebo with a 52-week prednisone taper (van Elteren p≤0·001, tocilizumab once a week vs placebo groups; p<0·05, tocilizumab-every-other-week vs placebo groups). Tocilizumab-based regimens restored clinical remission among patients who experienced relapse in part two and were treated (median time to remission: 15 days for tocilizumab alone [n=17]; 16 days for tocilizumab plus glucocorticoids [n=36]; and 54 days for glucocorticoids alone [n=27]). No new or unexpected safety findings were reported over the full 3 years of the study. INTERPRETATION: Giant cell arteritis remains a chronic disease that entails ongoing management and careful vigilance for disease relapse, but continuous indefinite treatment with immunosuppressive drugs is not required for all patients. A substantial proportion of patients treated with tocilizumab for one year maintain drug-free remission during the two years after tocilizumab cessation. For patients who experience relapse, tocilizumab can be used to manage relapses, but it remains prudent to include prednisone for patients who experience relapse because of the risk for vision loss. FUNDING: F Hoffmann-La Roche.

Symptom-based stratification of patients with primary Sjögren's syndrome: multi-dimensional characterisation of international observational cohorts and reanalyses of randomised clinical trials.

BACKGROUND: Heterogeneity is a major obstacle to developing effective treatments for patients with primary Sjögren's syndrome. We aimed to develop a robust method for stratification, exploiting heterogeneity in patient-reported symptoms, and to relate these differences to pathobiology and therapeutic response. METHODS: We did hierarchical cluster analysis using five common symptoms associated with primary Sjögren's syndrome (pain, fatigue, dryness, anxiety, and depression), followed by multinomial logistic regression to identify subgroups in the UK Primary Sjögren's Syndrome Registry (UKPSSR). We assessed clinical and biological differences between these subgroups, including transcriptional differences in peripheral blood. Patients from two independent validation cohorts in Norway and France were used to confirm patient stratification. Data from two phase 3 clinical trials were similarly stratified to assess the differences between subgroups in treatment response to hydroxychloroquine and rituximab. FINDINGS: In the UKPSSR cohort (n=608), we identified four subgroups: Low symptom burden (LSB), high symptom burden (HSB), dryness dominant with fatigue (DDF), and pain dominant with fatigue (PDF). Significant differences in peripheral blood lymphocyte counts, anti-SSA and anti-SSB antibody positivity, as well as serum IgG, κ-free light chain, ß2-microglobulin, and CXCL13 concentrations were observed between these subgroups, along with differentially expressed transcriptomic modules in peripheral blood. Similar findings were observed in the independent validation cohorts (n=396). Reanalysis of trial data stratifying patients into these subgroups suggested a treatment effect with hydroxychloroquine in the HSB subgroup and with rituximab in the DDF subgroup compared with placebo. INTERPRETATION: Stratification on the basis of patient-reported symptoms of patients with primary Sjögren's syndrome revealed distinct pathobiological endotypes with distinct responses to immunomodulatory treatments. Our data have important implications for clinical management, trial design, and therapeutic development. Similar stratification approaches might be useful for patients with other chronic immune-mediated diseases. FUNDING: UK Medical Research Council, British Sjogren's Syndrome Association, French Ministry of Health, Arthritis Research UK, Foundation for Research in Rheumatology. VIDEO ABSTRACT.